This invention relates to solenoid actuated fuel injectors for engines and, more particularly, to an injection valve seat/director formed as an integral dual function unit.
It is known in the art relating to solenoid actuated engine fuel injectors to provide a valve seat for engagement by a disk-like armature to cut off fuel flow through an injector. A separate fuel spray director may be provided with spray holes to direct an atomized spray of fuel from the valve seat into an engine. Typically, the valve seat and the spray director are separate components requiring individual forming and machining or other processing and requiring assembly in an injector with other components to form a completed structure ready for use. A simpler valve seat and spray director assembly involving less costly or reduced processing steps is desired.
The present invention provides an improved and simplified valve seat/director unit, which combines in an integral unit the functions of a valve seat and a fuel spray director. The unit is preferably made using electroforming and/or metal etching processes. The unit may be made in layers with the same or differing materials, if desired, and with differing thickness to best accomplish the purposes of the integral unit.
In an optional embodiment, a valve seat/director unit is formed as an integral multiple thickness unit for an engine fuel injector. The unit is essentially a flat plate with an outer portion including a rim or plurality of raised ribs, which are engagable with a spacer rim or other member of an injector for forming an external seal. A central portion includes a plurality of spray holes or openings surrounded on at least one side by a raised rib forming a valve seat. The seat may be varied in configuration for engagement by a solenoid valve disk or a plunger type valve as desired. The valve seat and the outer rim or ribs are preferably formed as coplanar surfaces with equal thickness through the plate. Intermediate portions of an upper surface are recessed to allow fuel flow to the valve seat but may include raised shapes for engaging a mating member.
The seat/director may be formed as an integral unit in any suitable manner. However, electroforming, metal etching or a combination of both are presently preferred methods. By these methods, a dual thickness valve seat/director unit may be formed by simple processing to finished dimensions without requiring further finishing steps. A simplified, cost efficient unit is thus provided, combining the features of separate valve seats and director plates while avoiding the machining or forming and assembly steps these separate components require.
These and other features and advantages of the invention will be more fully understood from the following description of certain specific embodiments of the invention taken together with the accompanying drawings.